Prosthetic limbs for the upper and lower extremities typically include a residual limb socket, an alignment system, and distal prosthetic components to complete the limb. For any prosthetic limb, the prosthetic socket is the portion of the prosthesis that is designed to fit on the residual limb and connect with the rest of the prosthetic components. The prosthetic socket grasps the residual limb and provides the functional connection to the distal components. If the prosthetic socket does not fit properly, it will inevitably be uncomfortable for the patient, even to a level of intolerability. Even the most sophisticated of prosthetic limb components will not serve the patient well, if the fit of the socket is unsatisfactory.
Conventional prosthetic sockets are typically custom made, making use of positive molds derived from a cast of the patient's limb. The positive mold, standing in for the patient's limb, is used to make the prosthetic socket and is often saved for future use by the prosthetic shop. Although the custom fitting and positive mold making process can work well, if performed by a highly skilled practitioner, the process and resulting positive mold can be quite costly, due in part to the time, space, and expense needed to make, store and ship the cumbersome positive mold.
Some of the shortcomings of the conventional approach to fabricating custom-fitted prosthetics are addressed by the development of a modular approach to socket assembly, as disclosed in U.S. Patent Application Publication No. 2013/0123940 of Hurley and Williams, filed on Nov. 13, 2012, and U.S. patent application Ser. No. 14/213,788 of Hurley and Williams, filed on Mar. 14, 2014. Modular components that vary in size and shape can be fabricated by modern, scalable manufacturing methods. Assembling these components into custom-fitted prosthetic sockets can occur within a single day, in contrast to the multiple weeks needed for conventional prosthetic socket fabrication methods. Nevertheless, challenges remain in the full implementation of a modular approach to prosthetic socket assembly. For example, manufacturing and assembly facilities, prosthetic socket clinical sites, and patients can often be widely scattered from each other geographically and logistically.
Therefore, it would be very desirable to have improved methods and apparatus for designing and manufacturing prosthetic sockets. Ideally, such improved methods and apparatus would be able to fully replace the use of positive molds with efficient and effective methods for fitting prosthetic sockets to patients' residual limbs. It would also be ideal if these methods and apparatus could reduce the transactional costs associated with the flow of information and components between patients, doctors, prosthetists and manufacturers. At least some of these objectives will be met by the embodiments described below.